The Guru of 3D posted a review on the Radeon HD 3870 X2
What you are here for today is that new mammal called the Radeon HD 3870 X2. Pretty cool stuff, as this is a multi-GPU solution on one PCB (one board). Yep, two graphics processors on one board, bridged, making it a "single" card, a card that because it's bridged will work on any mainboard with a fast enough PCIe slot .. and yes that's including NVIDIA's nForce series. Twice the performance of RV670 (Radeon HD 3870), twice the memory (2x512MB) boasting the HD 3870 X2 product in the high-end segment, aimed at you guys at an okay price.Radeon HD 3870 X2 review (HIS retail sample)